Pivoted fence with locating post

Abstract

A router and other cutting tools with a fixed center such as drills, shapers, milling machines, etc., used for cutting wood, metal or other materials, is provided with a fence mechanism for either a table or the base of a portable tool, for rapid and easy settings of the fence with respect to the center of the cutting tool. This is accomplished by a pivot mounting of the fence on a table or on a portable tool base, with respect to a block pivoted to the table or tool base, wherein the center of the pivot for the block and the center for the pivot for the fence are on opposite sides of the cutting tool and located on a line which passes through the tool center and the respective pivot locations. The desired spacing of the fence to the tool can be achieved using accurate spacers between the fence and the block, even with the tool being mounted in place. When used on a table, a curved slot in the table top, of predetermined shape and location with respect to the tool center, can be provided to receive a follower pin extending from the fence and function to move the fence in fence centered motion. The disclosure teaches how to develop such a curved guiding slot.

Claims

1. A fence mechanism providing rapid and simplified settings of a fence member with respect to the center of a rotary cutting tool, in which the cutting tool is mounted to rotate in line with a center point in a base member,

a base member having a center point providing a reference to the rotational axis of the cutting tool,

a fence member extending at least partially across said base member past said center point

a stop member to one side of said aperture for providing a rest which a first portion of the fence can contact for positioning,

a pivot connection between said fence member and said base member located on said fence member at the opposite side of said aperture from said stop member such that said fence member can be swung about said pivot connection into contact with said stop member with a central portion of said fence member intersecting the axis of rotation of the cutting tool,

whereby movement of said first portion of said fence member a predetermined distance away from said stop member will cause said central portion of said fence member to locate at a predetermined spacing from the tool axis of rotation so workpieces can be guided with respect to the rotating tool as the workpiece and tool are moved relative to each other.

2. A fence mechanism as defined in claim 1, wherein said base member is a base plate of a portable tool and said fence member is attached to said base plate.

3. A fence mechanism as defined in claim 1, wherein said base member is a table having an upper surface with said center point thereon and to which the rotary cutting tool is aligned, and

said fence member is mounted to the upper surface of said table.

4. A fence mechanism as defined in claim 3, wherein said table upper surface includes a curved slot located with respect to said stop member and said center point,

said fence member having a straight slot therein and said fence member pivot connection is fixed to said table surface and has a sliding connection to said straight slot,

a curved slot formed in said table surface, and a follower on said fence member which tracks along said curved slot.

5. A fence mechanism as defined in claim 1, wherein measuring means are associated with said stop member to provide precise spacing of said stop member and said first portion of said fence member, thereby to provide precise spacing between said central portion of said fence member and the rotary cutter regardless of the presence and/or size of the rotary cutter.

6. A fence mechanism as defined in claim 1, wherein said stop member includes a disc for contacting said first portion of said fence member.

7. For use with a rotary cutting tool mounted to rotate in an aperture in a base member, a fence mechanism for setting the position of a fence member with respect to the center of the rotary cutting tool, comprising

a base member having a central aperture providing a surrounding through which the cutting tool can project,

a fence member extending perpendicularly to and at least partially across said base member past said aperture,

a stop member to one side of said aperture for providing a rest which a first portion of the fence can contact for positioning,

a pivot connection between said fence member and said base member located on said fence member at the opposite side of said aperture from said stop member such that said fence member can be swung about said pivot connection into contact with said stop member with a central portion of said fence member extending across said aperture and intersecting the axis of rotation of a cutting tool when mounted,

whereby movement of said first portion of said fence member a predetermined distance away from said stop member will cause said central portion of said fence member to locate at a predetermined spacing from the tool axis of rotation so workpieces can be guided with respect to the rotating tool as the workpiece and tool are moved relative to each other.

8. A fence mechanism as defined in claim 7, wherein

said base member is a base plate of a portable tool and said fence member is attached to said base plate.

9. A fence mechanism as defined in claim 7, wherein

said table upper surface includes a curved slot located with respect to said stop member and said aperture,

said fence meber having a straight slot therein and said fence member pivot connection is fixed to said table surface and has a sliding connection to said straight slot,

a curved slot formed in said table surface, and a follower on said fence member which tracks along said curved slot.

10. A fence mechanism as defined in claim 9, wherein

said table upper surface includes a curved slot located with respect to said stop member and said aperture and said fence member pivot connection is a follower on said fence member which tracks along said slot.

11. The method of setting the position of a fence member with respect to the center of a rotary cutting tool mounted to rotate in an aperture in a base member, comprising

mounting a fence member extending perpendicularly to and at least partially across the base member and past the aperture,

locating a stop member to one side of the aperture providing a rest which a first portion of the fence can contact for positioning,

providing a pivot connection between the fence member and the base member which is located on the fence member at the opposite side of the aperture from the stop member such that the fence member can be swung about the pivot connection into contact with the stop member, thus locating a central portion of the fence member extending across the aperture and intersecting the axis of rotation for a cutting tool,

moving the first portion of the fence member a predetermined distance away from the stop member to cause the central portion of the fence member to locate at a predetermined spacing from the tool axis of rotation so workpieces can be guided with respect to the rotating tool as the workpiece and tool are moved relative to each other.